Some vehicle systems now engage in automatic or autonomous braking (i.e., without driver intervention) when an imminent collision is detected so that the impact may be avoided or its severity minimized. If the vehicle system automatically engages the brakes according to a constant and predetermined brake setting, however, then it can result in an overly conservative braking event where the vehicle stops well short of a target vehicle in front or the vehicle is decelerated to a much slower velocity than that of the target vehicle. In either case, the overly conservative automatic response of the vehicle system may be undesirable, as it can potentially subject the vehicle to a rear end crash by a trailing vehicle or to some other unwanted situation.